The Competition Squares Off

Although Vibroplex fought court battles with Coffe and later Bunnell, Martin and his business partner Albright could not ultimately prevent other bugs from appearing on the market. Popular legally introduced models included the Mecograph, McElroy, and Speed-X. Many "bootleg" models were found to be direct patent infringements and were successfully sued by Vibroplex. Eventually, many of these bugs were "licensed" by Albright for a fee.

coffe vertical


William O. Coffe patented a semiautomatic key at about the same time that Martin patented the Vibroplex. Coffe's vertical bug was called the "Mecograph." The Mecograph mechanism involved the release of spring tension to create a vibration, rather than pushing against a spring as did the Vibroplex. Vibroplex sued Coffe for patent infringement and lost, opening the door for legal competition. Coffe made very few of the original wood based Mecograph keys, but soon sold to Bellows who oriented the mechanism in a horizontal fashion on a brass base. Bellows produced several Mecograph models before Vibroplex bought him out, presumably to reduce competition.

In-line Mecograph

Mecograph did produce an inline model, the closest in appearance and function to the Vibroplex patent. Few survive today, and it is likely that few were produced.

1907 model right angle mecograph

This right angle Mecograph from 1907 features a sliding speed control and a flat brass finish. Many different variations were made.

right angle mecograph

The right angle Bellows Mecograph No.2 from 1909 was available in a striped "Mecograph" finish. A wonderful dovetailed wooden box either came with it or was offered as an accessory.

One of the four keys in this picture is a spy key, the others are not. In general, keys used in clandestine radios needed to be small and quiet. Most small keys available these days are novelty pieces and were not spy keys at all. See if you can tell which of these keys was really a spy key by clicking on the proper key! For further information on the real spy key, check out the special purpose or mission radio section at


Les Logan and Speed-X Bugs

Electro Mfg. began in Fresno, CA around 1927 and then moved to San Francisco. It is widely believed by collectors to have been the predecessor of Speed-X which began in San Francisco just after Electro disappeared. Speed-X began under Stewart Johnson, then was apparently bought by Les Logan. Much later, circa 1947, the company was bought by E.F. Johnson and moved to Minnesota. Speed-X made straight keys as well as bugs and practice sets. The ElectroBug is shown here.

electro-bug jr

The Electro-Bug Jr. was also made by Electro Mfg. and was similar to the ElectroBug, except that it lacks the electromagnetic assist to the lever that the ElectroBug had. Note the similarity to the Logan Speed-X Model 501.

logan model 501

This T-bar Les Logan Model 501 was made in San Francisco, CA and is a favorite among collectors. The Logan's Model 500 and E.F. Johnson's Model 114-501 were very similar.

1936A T-bar McElroy

T.R. McElroy

Telegraph keys by T.R. McElroy are highly sought after by collectors perhaps because of McElroy's personality and accomplishments. He holds the record for the world's fastest telegrapher, at over 75 words per minute! He manufactured several models of bugs during the late 1930's and early 1940's. Unlike Vibroplex, he did make straight keys as well. This is the 1936A McElroy. Tom French has published an excellent book on T.R. McElroy.

McElroy Junior

The Mac Junior is one of the rarest of the McElroy bugs for collectors to find. It is also one of the most poorly constructed, being stamped out of sheet metal rather than cast. This model appeared around 1936.

black crinkle S600

The S600 is one of the few bugs ever produced on a teardrop shaped base. Its unique construction makes it another collector's favorite. Several variations exist. Interestingly, most S600s are chrome plated, something which McElroy himself thought a poor idea earlier in his career.

T.R. McElroy Chronology, from "McElroy, World's Champion Radio Telegrapher", by Tom French

chrome S-600

This is the chrome version of the S600 most people expect to see. It certainly is a snappy looking bug. On the early T-bar bugs, McElroy cast into the bottom of the base that he is the worlds fastest telegrapher. On the S600 and later T-bar bugs, he simply includes that on the front label.


The Dunduplex

Thomas J. Dunn made the "Dunduplex" in 1909 and was eventually put out of business by Martin and Vibroplex on the basis of patent violations. This bug has a relatively small footprint and can be operated by using the paddles or pressing the buttons on top of the bridge near the paddles, hence the "duplex" part of the name. A single lever and a double lever variant were made.

Melehan Valiant

The Melehan Valiant

This hefty telegraph key is called the "Melehan Valiant" and was made around 1940. It is not a true semiautomatic key or bug. It has two completely independent vibrating arms on one base with two pivots on one support assembly. Some inventors had reasoned, if a flat spring could make the "dits" repeat, then two flat springs could make dits and "dahs" repeat. The Melehan Valiant, made by Melvin E. Hanson became the most well known of these fully automatic keys. The Melehan Valiant never really got a chance to catch on, though. Electronic keyers and computer chips outmoded most mechanical keying devices by the 1950's. For many of us, though we use electronic keyers and paddles, they cannot replace the charm and allure of the early straight keys, the massive keys of spark, and the bugs.

Dual Lever ATOZ Gray Single Lever ATOZ

A to Z Electric Novelty Company

The A to Z Electric Novelty Company, also known as ATOZ, was run by Max Levy of Chicago, Illinois. ATOZ was in business around 1914. The business was in direct patent violation of Vibroplex's patents, and was fairly quickly shutdown. ATOZ made a knockoff of the Vibroplex Original, which is the most common ATOZ found. At least two Dual Lever ATOZ bugs are still in collections. One model X ATOZ is believed to exist. ATOZ was probably the most blatant of the Vibroplex patent violators, having the audacity to call its version "The Improved Vibroplex" in large fancy letters right on the label on the bugs! The bug on the left is a dual lever ATOZ, and the one on the right is a gray base single lever, or Original ATOZ.

The usefulness of the transformer lies in the fact that electrical energy can be transferred from one circuit to another without direct connection, and in the process can be readily changed from one voltage level to another. A transformer can only be used with alternating current, since voltage is only induced in the secondary coil when the magnetic field is changing. The voltage induced in a coil will be proportional to the number of turns in the coils, and the resulting current will be inversely proportional to the number of turns. Adapted from "The Radio Amateur's Handbook", 1973.

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